5.3 compression ratio

[diverlloyd]

does anyone know what the compression ratio is for the 5.3 HO Vortec (310 hp)? and how much higher is it than the standard 5.3 C.I. block Vortec?

[jwalker]

Anything related to your truck's specs can be found at Chevrolet.com. I found your info in less than 30 seconds at this URL:

 

http://www.chevrolet.com/silverado/specifications/

[diverlloyd]

Thanks a lot for the reply. I noticed that they recommend 87 octane for all the 5.3s. My engine, the HO does not run so good on regular. Neither did my '00.